This application is a 35 USC 371 of PCT/JP00/04703 filed Jul. 13, 2000.
This invention is related to a sheet metal bending system which includes a press brake and a sheet metal support apparatus which supports the sheet metal work when the sheet metal is bent by the press brake and a method to store the control data and a computer readable memory medium which stores the control data.
In a press brake where bending process of a sheet metal and the like are performed by combined action of the punch and die, the rise (or jumping) of the work W accompanying the bending process occurs with the shoulder K of the die as the revolving center (refer FIG. 13).
In such a process in course of bending, depending on the size, sheet thickness, sheet material, the work may be bent due to the large mass of the jumped part. In order to prevent this flexure, the worker supported the work or the work was supported by a sheet metal support device that supported the work following its jump.
However, if it is made so that the revolving center of the support arm of this sheet metal support is also on the shoulder K of the die D, the trajectory may be made the same as the rise of the work W, but the structure does not allow to place the rotation axis member as a rotation center at the shoulder K of the die. Formerly, therefore, a link mechanism in Japanese patent 1511802 (JP63-61094) by the applicant of the present patent has been generally used.
Also, the control data of conventional sheet metal bending systems includes bending process data that control mainly the press brake and follow-up control data mainly for control of sheet metal support devices.
The bending process data includes the bending order which is process order of a plurality of bending processes to be made on the work, the punch type to be used in each bending process, the die type, the V breadth of the die, the D value which prescribes the target engagement position of the punch and the die in each bending process, and the L value which prescribes the target position of the back gauge which determines the position of the work so that the line of the work coincides with the bending axis of the punch and the die, and the like.
Also, the bending process data is prepared by an automatic bending programming device called BEND CAM based on, for instance, three face figures and three dimension CAD data of sheet metal products and stored in the processing data server called the host machine. To the host machine, more than one terminal machine which are press brakes are connected making it possible to supply processing data from the host to the terminal machine, and feedback the revised D value, revised L value which are values revised based on processing data of actual processing from the terminal machine to the host machine.
Also in the host machine, not only bending process data but manufacturing machine information, information of metal molds of punch and die, material information, three-dimensional figure information which may display three dimensional models of each sheet metal product by three dimensional CAD, and unfolded figures and the like of each sheet metal product and the like are stored.
In the follow-up control data, the necessity of the sheet metal support apparatus, the number of support arms used, the necessity of interference avoidance movement between the punch and the work when the punch and die are to be separated after the press, and a follow-up timer value which is the period during which the support arm is to be stopped at the follow-up end position.
In preparing these follow-up control data, the bending data is displayed on an input-output device called a press brake pendant and based on the displayed data the worker judges and inputs the necessity of the sheet metal support device, the number of support arms used, the necessity of interference avoidance movement between the punch and the work when the punch and die are separated after the press, and the follow-up timer value to the input device provided on the sheet metal support device.
However, in the link type sheet metal support device, there is a problem that a three axis control device, a height direction control device, a length direction control device and a rotation angle control device for the die height, V width and rise of the work will be required making the total unit a complex and elaborate and costly arrangement.
Also, arranging a large sheet metal support device in front of the press brake may impair the workability.
Also, there is a problem that in the past the bending process data for conventional sheet metal bending systems were stored in the memory device of the host machine and could be used commonly by each terminal machine connected to the host machine but for follow-up control data, the follow-up control data is stored in each sheet metal support device and cannot be used by other sheet metal support devices.
The object of this invention is, in view of the problems in the conventional technology, to provide a sheet metal bending system provided with a sheet metal support device which may accurately follow-up the rise of the work when bent and a memory storage from which the stored control data may be read out by a computer.
The other object of this invention is to provide a read-out computer memory medium which stores methods of storage of control data of the sheet metal bending system and control data of the sheet metal bending system, which enable reuse of follow-up control data which is the control data used by the sheet metal support device together with the press brake, by not only that sheet metal support device but by other sheet metal support devices. With this arrangement time may be shortened and the rate of operation of the sheet metal bending system may be improved.
The present invention is made due to heretofore problems mentioned above. The sheet metal bending system of the present invention has a press brake which bends the work along the bending axis by cooperative action of a punch and die which approaches and separates from each other and a sheet metal support device which supports the work being bent by at least one support arm provided on the front face of this press brake. And the sheet metal support device has a rotation mechanism which rotates the support arm centered around the first rotation axis while rotating the first rotation axis around the second rotation axis and a linear movement mechanism which moves the second rotation axis in the direction of the approach and separation of the punch and die.
In this system, by controlling the rotating mechanism and the linear movement mechanism, the position of the support arm in the direction of the approach and separation of the punch and die and angle of the support arm may be made to coincide with those of the work being bent.
Also, in the method to generate the control data for controlling the sheet metal bending system provided with a press brake and sheet metal support device of the present invention, the press brake has a punch and a die which bends along the bending line on the sheet metal by approaching and separating from each other. And the punch and die has a bending axis. The press brake is provided with a back gauge that determines the position of the sheet metal so that the bending axis coincides with the bending line. The sheet metal support device supports the sheet metal in front of the press brake and is provided with a support arm free to rotate around a rotation axis parallel to the bending axis. The control data is to control the approach and separation motion of the punch and die in order to control the approach and separation motion of the punch and die and at least the rotation movement of the support arm in order to perform a plurality of bending processes to produce sheet metal parts (parts) with a plurality of bending lines. And in the method, the ID of the sheet metal parts are generated; the bending order which is the order of bending the plurality of bending lines and of the punch and die type for bending each bending line is determined; the D value which prescribes the punch and die target engagement position and generation of the L value which prescribes the target position of the back gauge in each bending process is generated; the Z direction position of the support arm at the start of the bending in each bending process based on the Z axis direction size of the die to be used is determined; the target Z axis direction position and the target rotation position "THgr" of the support arm in each bending process based on the D value which prescribes the target engagement position of the punch and die and the V width of the die (and the thickness of the sheet) are determined; and the type of the punch and die, and the D value and L value, the height position of the sheet metal support at the start of the process and the target height position and the target rotation position in the bending order and each bending process, are stored in the memory medium together with the sheet metal parts ID
By the arrangement, according to the method of generating the control data for controlling the sheet metal bending system provided with a press brake and a sheet metal support device of the present invention, not only bending control data such as D value, L value to control the press brake but also control data for controlling the sheet metal support apparatus may be reused on basis of the sheet metal parts ID.
A computer readable recording medium which stores control data to control the movement of a sheet metal bending system provided with a press brake and sheet metal support device has a construction as follows. The press brake is provided with a punch and die which by mutual approach to and separation from each other bends the sheet metal along the bending line, and is provided with a back gauge to position the sheet metal against the punch and die. And the sheet metal support device supports the sheet metal in front of the press brake and is provided with a support arm that may be rotated freely centered on a rotation axis parallel to the bending axis. The control data is a control data for controlling the approach and separation movement of the punch and die and at least the rotation of the support arm in the bending process which include a plurality of bending stages to produce sheet metal parts which possess a plurality of bending lines, and wherein, the control data comprising: an ID of the sheet metal parts; a process number which is related to the ID and specifies the ith bending process of a plurality of bending processes; a D value which is related to the process number and specifies the target engagement position of the punch and die in the ith bending process; a L value which is related to the process number and specifies the target position of the back gauge in the ith bending process; a V width of the die that is related to the process number and to be used in the ith bending process; a target rotation position xcex8 of the sheet metal support which is related to the process number and corresponds to the D value which specifies the target engagement position of the punch and die and the V width of the die (and the thickness of the work) in the ith bending process.
With the arrangement, by the computer readable recording medium which stores the control data to control the action of the sheet metal bending system provided with the press brake and sheet metal support device of the present invention, not only the bending control data such as the D value, L value and the like but the follow-up control data for controlling the sheet metal support device may be reused on basis of the sheet metal parts ID.
It is preferable that the sheet metal support be made free to move in the direction that the punch and die approach and separate.
It is preferable that the control data is related to the process number and possess punch and die data that prescribe the punch type and die type to be used in the ith bending process.
In the control data, it is preferable that at least one of the following is provided.
the compensation number xcex4xcex8 of the target rotation position of the sheet metal support in the ith bending process, which number is linked to the process number;
the initial position of the sheet metal support in the ith bending process, which position is linked to the process number;
the number (including zero) of sheet metal supports in the ith bending process, which number is linked to the process number;
the interference avoidance motion pattern of the sheet metal support in the ith bending process, which is linked to the process number, which pattern is linked to the process number; and
the disengagement position S and the disengagement angle xcex4 of the sheet metal support in the ith bending process, which position and angle are linked to the process number.